Several residents living near Glendale Avenue in Casper are worried that new development proposed nearby would alter the flood plain and worsen the danger to their homes.

"Flood insurance rates went up the month after Glendale flooded (in 2005)," resident Dianna Madvig told the Casper City Council on Tuesday. Madvig and half a dozen of her neighbors protested a proposed 44-acre, 137-unit development during a public hearing that lasted nearly five hours.

"We've had two major floods in eight years," she said. "We have seen an immediate impact in the last two years."

Madvig and her neighbors say their flood insurance rates have skyrocketed, from about $250 a year to more than $1,300 a year.

Paul Osman, chairman of the Flood Insurance Committee of the Association of State Floodplain Managers, said last week that flood insurance premiums set by the federal government have not gone up.

"If you are sitting right outside a flood zone and the risk zone on the map increases, your premiums should not change," Osman said. "FEMA has a grandfather clause that says as long as you remain in the same flood zone, your premiums will not change, regardless of the flood risk. You can be flooded every year and your premiums will remain the same."

Osman said private carriers may have raised rates to recuperate losses from Hurricane Katrina in 2005.

Craig Collins, associate planner for the city, said the city's flood plain maps were redrawn in 2004, but had not changed significantly since the previous maps were done in 1982. He said the city will be using the 2004 map for a long time. Eastdale Creek, which runs along Glendale, is still in a 100-year flood zone, Collins said.

In early August 2005, one inch of rainfall caused severe flooding on Glendale when a dam overflowed, forcing some residents to evacuate their homes. A rushing river of muddy-brown water swept away parked cars after overwhelming the drainage system.

"When you get a storm like that one in Aug. 2005, the system cannot keep up with the amount of water," said Lt. Stewart Anderson, Natrona County emergency management coordinator.

The city council passed the proposed development on first reading, under the condition that the drainage and area traffic concerns be addressed before the third and final reading.

City Manager Tom Forslund said the city plans to redo the Glendale drainage and 26th Street extension by the summer of 2011. He said the city council can choose to move up the date on the Glendale projects, but it would push back other street improvement projects in the Fort Caspar area, the David Street extension and Center Street improvements.

Madvig said she and her neighbors can't wait until 2011 for the drainage to improve.

"Our homes are in jeopardy every time it rains," Madvig said. "It absolutely does not make sense to approve these plans and say, 'We probably won't flood for another eight years.'"

Reporter John Morgan can be reached at (307) 266-0614 or john.morgan@casperstartribune.net.